Semi-frozen beverage dispensing apparatus

ABSTRACT

A method of controlling semi-frozen liquid beverage in a dispensing machine having a bowl to contain the beverage, a motor to turn a helical auger blade within the bowl to scrape the semi-frozen beverage, and a compressor to cool the beverage. The method includes the steps of actuating the compressor to the bowl until the temperature of the beverage is cool to reach an initial set point. The compressor is deactivated after temperature of the beverage is cooled at or below a set point. Torque on the motor caused by resistance to the auger blade is sensed after a defined time period following switching off of the compressor. The compressor is activated if the torque on the motor is below a certain level and the temperature set point is lowered from the initial set point to a lower set point in order to cool the product.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to a semi-frozen liquid beveragedispensing machine and a method of controlling semi-frozen liquidbeverage in a dispensing machine.

2. Prior Art Various known types of beverage devices dispensesemi-frozen and chilled liquid beverages.

The chilled beverages may take various names such as “sicilian granita”or “slushies”. The consistency of the beverage product is a thick slushthat stands up in a cup or container. The beverage dispensing deviceitself typically includes a cylinder within a transparent bowl thatvisually displays the product wherein the cylinder is refrigerated withrefrigerants. In one arrangement, a hollow stainless steel cylinder isarranged horizontally in the bowl. A helical blade driven by an electricmotor continually moves across the external portion of the cylinder toscrape offer “harvest” frozen crystals formed by the refrigerationprocess. Accordingly, over time, the entire contents of the bowl becomesemi-frozen and the product is mixed while in the bowl.

The solids content (sometimes described as “brix”) and consistency ofthe semi-frozen product should be maintained. If the product is toowarm, it turns liquid. If the beverage is cooled too much, the beveragethickness becomes excessive.

Controls have been placed on the refrigerating system in a number ofways. In one arrangement, the compressor will switch off in response toachieving a set temperature. In another arrangement, torque systemsmeasure viscosity of the product through resistance on a dasher or drivemotor. The resistance is measured either mechanically or electronicallyand the measurement is constant whether the compressor is running ornot. This type of measurement is somewhat inefficient and causes shortcycling of the compressor. While measuring torque in this manner, it canbe measuring frost build-up on the evaporator and not the viscosity ofthe mass in the bowl causing false consistency results and short cyclingthe compressor.

It is known that when product is placed in the bowl in the liquid state,it will initially be brought down in temperature until it reaches thefreeze-down stage. Thereafter, it has been observed that the productbegins to thin down. For example, a product that has excellent thicknessimmediately following an initial freeze-down could be runny severalhours later even if the temperature is held constant. This may be due tomany factors which include the growth of ice crystals on the evaporatorover time. As water is extracted from the solution to maintain icecrystal growth, more of the syrup components are freed and act aslubricants which stimulate growth of the ice crystals. This effect,combined with a greater disparity between the size of the solid icecrystals and the remaining liquid components results in the thinningdown of the product. Accordingly, it has been found that the use oftemperature only as a control is unsatisfactory.

In existing torque control systems, a gear motor places an auger driveaxle several inches away and radially offset from an electric motor. Themotor dangles below the motor drive axle and is allowed several inchesof radial arch motion. When the motor is off, when there is noresistance on the auger, the motor hangs directly below the auger driveaxle, tripping a limit switch that is mounted to the right of the motor.

The control circuit for the bowl refrigeration is run through the limitswitch, causing refrigeration suddenly to open (and the compressor tostart) if the motor is dead hanging. When the auger encountersresistance, the electric motor actually rotates radially in a clockwisemotion through an arc (defined by the length of offset between the augerdrive axle and the motor). This clockwise rotation causes contact withthe limit switch to be broken, shutting off refrigeration for the bowl.

It is desirable to provide a system to control product density ratherthan a system to simply control the temperature in the bowl.

It is desirable to provide a system to control product density ratherthan a system to monitor and control frost build-up on the evaporator.

The liquid to replenish the bowl must be refilled from time to time. Ina typical dispenser, the top of the bowl is removed and liquid isreplenished by an attendant. To refill, the liquid mixture is pouredfrom a bulk storage container into the open top by an attendant.

The liquid may be packaged for storage and transportation in variousways. In one type of bulk packaging, a flexible inner storage membrane,such as plastic, is retained within a rigid package such as a cardboardor corrugated box. Various delivery systems are known, for example,those contained in the Applicant's pending U.S. patent application Ser.Nos. 09/650,586 and 09/814,081, each of which is incorporated herein byreference.

There remains a need to provide an integrated beverage dispenser and astorage and delivery mechanism for bulk packaging.

It is also desirable to increase production capacity of a semi-frozenliquid beverage dispenser beyond the capacity of the particular bowl andautomatically fill the bowl from bulk storage.

It is also desirable to replenish liquid in the bowl by automaticallyrefilling the liquid dispenser device.

Existing bowl designs for dispensing apparatus will occasionally have atendency to have inefficient fluid dynamics and consequently developdead spots wherein icebergs may form thereby causing an unsightly andunappetizing appearance. One solution in the past has been to addadditional mechanical mixing sources to minimize this effect.

It would be desirable to provide a novel type of bowl design having ageometric shape which would create sufficient fluid dynamics toeliminate the foregoing inefficiencies and maintain a more consistentsemi-frozen beverage product.

In existing designs it is difficult to evacuate all liquid from the bowlthus causing a mess when removing the bowl for cleaning. Some systemsemploy devices to adjust the bowl at such times.

It would be desirable to have a bowl design that efficiently evacuatesthe liquid without any manipulation of the bowl.

In existing designs ambient air is allowed to come in contact with theproduct with all its possible air born contaminates.

It would be desirable to have a system that filtered the air that camein contact with the product.

Existing systems rely on the operator to manually adjust the machine forvariables such as consistency and brix for each flavor type.

It would be desirable to have a system that identified the product andautomatically adjusted torque and mix ratios.

In existing systems the operator has to manipulate a gasket and placesame on the machine to create a seal between the bowl and the machine.

It would be desirable to have a gasket system that attaches easily tothe bowl before affixing it to the machine.

SUMMARY OF THE INVENTION

The present invention is a semi-frozen liquid beverage dispensing deviceand process. The dispenser includes a utility compartment having anoperator control interface panel and may include various displays.

The dispenser will include at least one bowl and in the presentembodiment, a pair of bowls for dispensing of semi-frozen liquidbeverages. Each bowl includes a lever which controls dispensing of thebeverage.

The dispenser includes an integrated mix storage area having at leastone refrigerated storage cavity to receive a bulk storage container foreach bowl. A fluid passageway will extend between the bowl and the bulkstorage container so that the bowl will be replenished from time totime. A pump is used to transport liquid product from the bulk storagecontainer through the tube and into the respective bowl.

A cylindrical evaporator extends or projects horizontally into eachbowl. A compressor is used to cool the cylindrical evaporator and, inturn, to decrease the temperature of the beverage in the bowl.

An external helical auger blade rotates around the exterior of thecylindrical evaporator to scrape the semi-frozen beverage therefrom. Acorresponding internal auger may be utilized to scrape the internalsurface of the cylindrical evaporator.

The bowl itself may be at a slight pitch for improved draining andproduct delivery.

The auger blade is rotated by a drive axle which, in turn, is rotated byan electric gear motor which hangs from the drive axle. As the augerblade encounters resistance, the resistance will tend to rotate the gearmotor. As resistance decreases, the gear motor will tend to rotatetoward bottom dead center.

The bowl has an elongated cylindrical body with a closed front with theexception of an opening for product delivery controlled by one of thelevers. The front and top of the bowl are partially domed and truncatedto enhance fluid dynamics. The top of the bowl is entirely closed andhas a receptacle which will receive a pin extending from the dispenserin order to lock the bowl in place in the cabinet. The back of the bowlis entirely open and will mate with the wall of the dispenser to form afluid tight seal.

The dispenser includes an RFID (Radio Frequency Identification) systemthat is capable of two-way communications with appropriately tagged bulkstorage containers and capable of monitoring two different containers inthe same mix storage cabinet. The communications will include suchthings as determining the bulk storage container characteristics andcausing internal machine adjustments to occur, initial freezetemperature set point, mix ratio of product to water, begin life cycleof the container, visually identify the flavor on a display, insureproduct is within code. The RFID system is also used to periodicallyretrieve technical and marketing/sales data with a smart card.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a semi-frozen liquid beveragedispensing device constructed in accordance with the present invention;

FIG. 2 illustrates a front view of the semi-frozen liquid beveragedispensing device shown in FIG. 1;

FIG. 3 illustrates a side view of the semi-frozen liquid beveragedispensing device shown in FIG. 1 with portions cut-away for ease ofcomprehension;

FIG. 4 illustrates a perspective view of a bowl apart from the liquidbeverage dispensing device;

FIG. 5 illustrates a side view of the bowl shown in FIG. 4;

FIG. 6 illustrates a back view of the bowl shown in FIG. 4; and

FIG. 7 is a flow chart diagram of a temperature and torque controlsystem which is a part of the semi-frozen liquid beverage dispensingapparatus of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The embodiments discussed herein are merely illustrative of specificmanners in which to make and use the invention and are not to beinterpreted as limiting the scope of the present invention.

While the invention has been described with a certain degree ofparticularity, it is to be noted that many modifications may be made inthe details of the invention's construction and the arrangement of itscomponents without departing from the spirit and scope of thisdisclosure. It is understood that the invention is not limited to theembodiments set forth herein for purposes of exemplification.

Referring to the drawings in detail, FIG. 1 illustrates a perspectiveview of a semi-frozen liquid beverage dispensing device 10 and FIG. 2illustrates a front view of the device 10 constructed in accordance withthe present invention. The dispenser 10 includes a utility compartment12 which may be configured in various ways. An operator controlinterface panel 14 will be used in connection with the process to bedescribed herein.

The dispenser 10 may also include various displays 16 and 18 foradvertising which may optionally be illuminated. The dispenser willinclude at least one bowl, and in the present embodiment, a pair ofbowls 20 and 22 for dispensing of the semi-frozen liquid beverages. Eachbowl includes a lever 26 and 28 which controls an opening in the bowl todispense the semi-frozen liquid beverage.

Optional cup dispensers 34 and 36 may be located between the bowls.

The dispenser 10 includes at least one integrated mix storage area, suchas refrigerated storage cavity 24 having a door 38. In the presentembodiment, the refrigerated storage cavity 24 will receive a pair ofbulk storage containers 30 of the liquid beverage. The bulk storagecontainers will typically include a plastic membrane surrounded by arigid cardboard or corrugated box. The refrigerated storage cavity 24retains the liquid beverages in refrigerated but not frozen conditions.

Each bulk storage container may contain a radio frequency identification(RFID) tag which emits a signal received at the dispenser to identifythe beverage, the desired temperature set point and other information.

A fluid passageway tube will extend between the bowl and the bulkstorage container so that the bowl may be replenished from time to timeas will be described herein.

FIG. 3 illustrates a side view of the dispenser which is partially cutaway in portions for ease of comprehension.

A pump 40 is used to transport liquid from the bulk storage containerthrough the tube and into the respective bowl. A clock and timer (notvisible) is associated with the timer to track times of delivery andgive an indication of volume of delivery.

An optional sensor (not shown) would be capable of sensing liquid levelof the semi-frozen beverage in the bowl 20 or 22 with the sensorconnected to the pump. When the liquid level is below the sensor, thepump 40 would be activated delivering fresh beverage into the bowl.

A stainless steel cylindrical evaporator 50 extends or projectshorizontally into each of the bowls 20 and 22. A compressor locatedabove the bowls in a refrigeration assembly 42 is utilized to cool thecylindrical evaporator and, in turn, to decrease the temperature of thebeverage in the bowl. A single compressor may be used to refrigerateboth bowls 20 and 22.

An external helical auger blade 52 rotates around the exterior of thecylindrical evaporator to scrape the semi-frozen beverage therefrom. Thehelical auger blade 52 is coaxial with the cylinder. Accordingly, as thebeverage decreases in temperature and moves to a semi-frozen state, theauger blade scrapes the cylinder and, at the same time, mixes theproduct in the bowl. A corresponding internal auger blade (not visible)may also be utilized to scrape the internal surface of the cylindricalevaporator 50.

In the embodiment shown, the bowls 20 and 22 are not parallel to a base32 of bowl tray 32 but are at a slight pitch, in this case approximately2° to 3°, for improved draining.

The auger blade 52 is rotated by a drive axle 54.

The drive axle 54 is, in turn, rotated by an electric gear motor 58which hangs from the drive axle. As the auger blade encountersresistance, it will tend to rotate the gear motor. As resistancedecreases, it will rotate toward bottom dead center.

FIG. 4 shows a perspective view and FIG. 5 shows a side view of one ofthe bowls 20 of the dispenser. The bowl has an elongated cylindricalbody with a closed front 70 with the exception of an opening for productdelivery which is controlled by the lever 26 (not seen in FIGS. 4 or 5).

The front and top are partially domed and truncated to enhance fluiddynamics. The top of the bowl is entirely closed and has a receptacle 74which will receive a pin extending from the dispenser in order to lockthe bowl in place. The back 76 is entirely open and includes a gasketwhich will mate with a wall of the dispenser to form a fluid tight seal.

With the bowl design of the present invention, it is possible topressurize the bowl for use of a carbonated beverage.

FIG. 7 illustrates a flow diagram of the refrigeration control processof the present invention. Three separate independent sub-processes aredisclosed and utilized. As seen in FIG. 7, during an initial freeze downshown at 80, the operator will load an initial freeze down set pointtemperature into a set point control. Alternatively, an initial freezedown temperature set point will be automatically loaded into thecontroller. During initial freeze down, the product will be brought froma completely liquid state to a thick slush. In one example, the beverageproduct will achieve an acceptable thickness at about 31° F.

During the refrigeration mode, the compressor will be started to coolthe beverage in the bowl. A sensor will determine whether the beveragetemperature is at or below the set point as illustrated at diamond 84.If the beverage is at or below the set point, no further action will betaken. If the beverage temperature is not at or below the set point, thedebounce timer procedure will be started. In this case, a timer will beinitiated to maintain the temperature for a certain period of time, suchas 30 seconds, as shown at diamond 86. Once the debounce timer hasexpired, the compressor will be activated to refrigerate the beverage asshown at box 88. As seen in the sub-process of the falling mode routine,a sensor, such as a mechanical limit switch, potentiometer, strain gaugeor other sensing device will monitor torque on the motor 58. In theevent that the liquid product is too thin, a reduced torque (or undertorque) as described on the electric motor will cause the limit switchto be tripped as seen at diamond 90. If the limit switch is tripped,this will be a yes response as shown at box 90. If the under torquecondition is sensed, a timer will be run for a period of time, such as 2minutes, to ensure the validity of the under torque condition, as shownat diamond 92.

Once the time period has expired, the set point will be lowered by apre-configured amount (stored in the machine's setup parameters), suchas 0.5° F. as shown at box 94.

If the refrigeration system has cycled from on to off since the lasttime the set point was lowered, then the procedure will recycle to thebeginning as shown at box 96.

The third independent sub-process is shown in the rising mode routine.The run time of the pump 40 is monitored in order to give an indicationof fresh liquid beverage being pumped from a bulk storage container intoone of the bowls. As an alternative to a timer system, the volume ofliquid may be monitored. This procedure is shown at box 100.

When a predetermined volume has been added to the bowl, therefrigeration set point will be raised, for example 1° F. as shown atbox 102.

A determination will then be made if the set point is higher than theinitial freeze down temperature set point as shown at diamond 104. Ifthe answer is no, the procedure will recycle.

If the answer is yes, then the initial freeze down temperature set pointwill be loaded as the new set point as shown at box 106. Thereafter, theprocedure will recycle to the beginning again. With the foregoingprocedures, not only will the temperature be monitored and maintained,but the viscosity or thickness of the product will be maintained.

Whereas, the present invention has been described in relation to thedrawings attached hereto, it should be understood that other and furthermodifications, apart from those shown or suggested herein, may be madewithin the spirit and scope of this invention.

What is claimed is:
 1. A bowl for a beverage dispenser, which bowlcomprises: an elongated cylindrical body; an entirely open back capableof mating with said dispenser; a closed top; and a closed, partiallydomed front.
 2. A bowl for a beverage dispenser as set forth in claim 1wherein an axis of said cylindrical body is at an angle to horizontalplane of said dispenser.
 3. A bowl for a beverage dispenser as set forthin claim 1 wherein said cylindrical body has a receptacle port toreceive a pin extending from said dispenser in order to lock said bowlin place.
 4. A bowl for a beverage dispenser as set forth in claim 1wherein said bowl receives a cylindrical evaporator through saidentirely open back.
 5. A bowl for a beverage dispenser, which bowlcomprises: an elongated cylindrical body wherein an axis of saidelongated cylindrical body is at an angle to a horizontal plane of saiddispenser; an open back capable of mating with said dispenser; a closedtop; and a closed, partially domed front.
 6. A bowl for a beveragedispenser as set forth in claim 5 wherein said cylindrical body has areceptacle port to receive a pin extending from said dispenser in orderto lock said bowl in place.
 7. A bowl for a beverage dispenser as setforth in claim 5 wherein said bowl receives a cylindrical evaporatorthrough said entirely open back.
 8. A bowl for a beverage dispenser,which bowl comprises: an elongated cylindrical body, wherein saidcylindrical body has a receptacle port to receive a pin extending fromsaid dispenser in order to lock said bowl in place; an open back capableof mating with said dispenser; and a closed, partially domed front.
 9. Abowl for a beverage dispenser as set forth in claim 8 wherein an axis ofsaid cylindrical body is at an angle to a horizontal plane of saiddispenser.
 10. A bowl for a beverage dispenser as set forth in claim 8wherein said bowl receives a cylindrical evaporator through said openback.